Programmable peripheral switch

Abstract

A peripheral switch (62) is electrically interposed between a peripheral device (10) and a plurality of computing devices respectively coupled to host computer ports (70a)-(70N). The peripheral switch (62) includes host computer port state sensing means (110) for determining a state of each host computer port (70a)-(70N) and providing a communication path to the peripheral device (10) from a host computer port (70a)-(70N) at a state indicative of a server computer being coupled thereto. The peripheral switch (62) further includes local handshaking means (120) for simulating communications from a server computer to peripheral device (10) if none of host computer ports (70a)-(70N) are determined to be coupled to a server computer.

Description

BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The invention described herein is related to switching devices for sharing a peripheral device among a plurality of computing devices. More specifically, the present invention selectively connects a peripheral device to one of a plurality of computing devices that presents a predetermined state at a communication port thereof and for simulating an active communication link between a computing device and the peripheral device when a computing device at the predetermined state is not available among the plurality of computing devices. [0003] 2. Description of the Prior Art [0004] Referring to FIG. 1, there is shown an exemplary network architecture found in, for example, tactical military environments. The network consists of a plurality of computing devices, such as single board computer (SBCs) 50a-50h electrically coupled to back plane 40 and mechanically secured within chassis 30. Each computing device 50a-50h is e...

AI Technical Summary

Problems solved by technology

It is apparent from FIG. 1 that the redundancy of the components of the depicted network can be extremely costly.

However, in some applications, the parallel structure, i.e., each single board computer 50a-50h coupled to its own PLGR 10a-10h, respectively, may be necessary or unavoidable.

Such switches may be useful for simple networks, but may not be used for distributing the ftnctionality of the peripheral to a number of differently configured computer systems, each requiring a unique communication protocol.

Moreover, the peripheral switch of Gordon cannot be effectively utilized to establish a communication between a peripheral requiring a particular host computer signature and a particular computing device in possession of the host computer signature.

However, if the peripheral were such that it would change state depending on the availability and operating status of a host (e.g., going into a “sleep” state when a host does not require it), a network incorporating the switch of Hastings would behave erratically when the peripheral automatically changed its operating mode and a host was expecting a “ready” peripheral with which to connect.

Thus, the switch disclosed by Osakada, et al. has limited applicability when the peripheral actively searches its connection for a specific host signature.

Further, the switch of Osakada, et al. does not provide means for preventing the peripheral from reverting to a secondary mode of operation should there be a failure to find a host of the specified signature.

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